LED Turn Signal Bulbs Flashing Too Fast? Causes & Easy Fixes

If you've got LED turn signal bulbs, you may have experienced something known as hyper-flashing. Unfortunately, this is a common problem when you switch from incandescent or halogen bulbs to LED ones.

Seeing your turn signals blinking feels a little bit frustrating, too, especially when you're expecting brighter illumination, longer life, and an energy-efficient solution. However, it does not mean your choice was wrong or that there is any kind of issue with your vehicle. Most compatibility issues are resolved quickly with the right approach.

The good news is we're here to help you fix hyper-flashing. In this blog, we will cover every detail that a beginner or an average-level person needs to know.

What Causes LED Turn Signal Bulbs to Flash Too Fast?

Hyper-flashing occurs due to the low power consumption of LEDs compared to traditional incandescent or halogen bulbs. Advanced vehicles have a smart monitoring system that actively tracks the power drawn by the turn signal bulb.

Upon noticing lower power consumption than expected, the monitoring system may misinterpret the bulb as faulty, even though it's working properly. This faster blinking is actually an intentional warning sign, triggered by the vehicle to alert the driver regarding bulb failure.

The same happens after switching from halogen to LED bulbs. However, electrical load is the most common but not the final cause of hyper-flashing. Bulb incompatibility, poor wiring connections, and damaged sockets also contribute to the issue.

How to Diagnose a Fast Flashing Quickly?

Blinking may affect one or both lights, and the underlying cause may vary depending on the specific signs and symptoms. Before you upgrade or fix LED turn signal bulbs, it is important to understand the underlying cause so you can choose the right solution tailored to the problem.

How to Fix LED Turn Signaling Hyper-Flashing?

There are various ways to make an LED turn signal hyper-flash, depending on the underlying cause. The best solution depends on your vehicle's turn signal system, as some models support relay replacement while others may need additional components to restore.

Installing the Load Resistors

One of the most effective ways to restore the flashing rate is to install load resistors. These resistors provide the electrical load that your vehicle expects from factory-installed bulbs, allowing the turn signals to return to their normal flash rate.

To properly install load resistors, begin by acquiring new 50W 6 OHM load resistors. Next, you'll need to determine whether you have a single-filament or a dual-filament application. In both cases, the resistor must be connected in parallel with the turn signal wiring, not in series, to properly simulate the original bulb load.

If you have a single filament, tap the load resistor wires that rest between the positive and negative wires. However, if you're working with a dual filament, you'll notice three wires: one negative, one high-filament positive, and one low-filament positive. This will again require you to tap the load resistor, and it's most likely located between the positive high filament and negative wires.

Please note: If tapping between the positive high filament and negative wires doesn't work, remove the wires and try again by tapping the other power wire. At most, this will cause you to tap the lead resistor up to two times.

Occasionally, you might try the hyper-flashing resistor installation in both configurations, but you still have not solved the hyper-flash issue. In this scenario, your connection could be the issue. To fix this issue, make sure the metal wire from the resistor is making solid contact with the factory wiring.

Merge your wires by using a wire stripper to strip back the rubber coating on the wire. This will expose the bare wire to tap the resistor in line. Once you've successfully merged the wires, use electrical tape or solder with heat-shrink tubing to cover the connection. Finally, mount the resistor with zip ties or self-tapping screws to secure it to the frame. Do not let the resistor touch any plastic or other wires, as they get very hot and can melt other components.

Also Read: Why LED Turn Signals Need Resistors

Upgrading to an LED-Compatible Flasher Relay

Upgrading the factory flasher relay with an LED-compatible relay is another reliable solution for vehicles that support relay replacement. Unlike load resistors, this approach simply requires fewer modifications to the wiring to restore the correct flash rate for all turn signals using a single component. Make sure your vehicle uses a replaceable flasher relay.

To begin, purchase an LED flasher relay upgrade kit. Next, remove the shroud and bezel fascia above your turn signal indicators. Unsnap the upper plastic panel from your steering column.

Take a Phillips head screwdriver and remove the screws that are holding the instrument panel in place, followed by removing the instrument panel. Once you've located the flasher relay, remove it and the anchoring nut with a 10mm wrench. Take the relay end and insert it into the relay clip slot. Plug in the new relay, and then reattach the bracket with your 10 mm wrench. Make sure your chosen hyper-flashing with a relay solution works, then reassemble everything using the reverse order.

Not all vehicles have a changeable flasher relay. Most newer vehicles are controlled by the BCM computer instead of a flasher.

Load Resistors vs. Flasher Relay Solutions

Upgrading to an LED Flasher Relay

Another method to eliminate hyper-flashing is by replacing the standard flasher relay with an LED-compatible relay. The flasher relay is responsible for controlling the blink rate of your turn signals.

1. Installation: Replacing the flasher relay is generally easier than installing resistors. Locate your vehicle's existing relay (often found under the dashboard or near the fuse box) and swap it out for an LED-compatible one.
2. Consideration: This solution is more straightforward and does not involve additional wiring or heat concerns. However, it's essential to ensure you purchase the correct relay compatible with your vehicle model.

How to Prevent Hyper Flashing: Instructions + Checklist

To prevent hyper-flashing in the future, choose LED bulbs that are compatible with your vehicle's electronics. Following a few simple checks before installation can help you avoid unnecessary troubleshooting later.

1. Choose LED bulbs with built-in resistors or CAN Bus compatibility, if required
2. Verify the correct bulb size and vehicle compatibility before purchasing.
3. Use high-quality LED bulbs and compatible installation components.
4. Avoid mixing LED and incandescent bulbs on the same turn-signal circuit unless recommended by the manufacturer.
5. Ensure all bulb sockets and electrical connections are clean and secure before installation.
6. Test the turn signals immediately after installation to confirm the flash rate is normal.

Conclusion

Hyper-flashing after upgrading to LED turn signal bulbs is usually caused by low power consumption, compatibility issues, or wiring problems rather than a defective bulb. Correctly diagnosing the symptoms and using the appropriate solution, such as load resistors, an LED-compatible flasher relay, or CAN Bus components, can restore the normal flash rate and reliable operation. If you're planning an upgrade or need compatible accessories, Underground Lighting offers LED turn signal bulbs, load resistors, and flasher relays designed for dependable performance and easier installation.